Rozhen Observation Calendar

Which nights are best for a target over the coming weeks. The astronomy mark (darkness × altitude × Moon) is computed for every night; the weather and the overall mark exist only where Open-Meteo has a forecast (the next four days) or ERA5 history (past nights) — the rest is honestly blank.

Best nights for Triangulum Pinwheel: 01-13 (100), 01-14 (100), 01-15 (100), 01-16 (100), 01-17 (100) — by astronomy; check the weather when the night is within four days.

2047-01-10astronomy score per night — click a bar for that night2047-02-08

night of	astronomy	weather	overall	best window	highest	dark h	Moon	Moon sep.
2047-01-10 Thu	40	—	unknown	18:50–00:05 (marginal, 5.25 h)	79.2° 18:35	11.33	98%	64.5°
2047-01-11 Fri	57	—	unknown	18:50–21:05 (good, 2.25 h)	79.2° 18:35	11.31	100%	77.5°
2047-01-12 Sat	75	—	unknown	18:55–22:30 (good, 3.58 h)	79.2° 18:30	11.29	99%	90.8°
2047-01-13 Sun	100	—	unknown	18:55–23:35 (good, 4.67 h)	79.2° 18:25	11.27	96%	104.3°
2047-01-14 Mon	100	—	unknown	18:55–23:40 (good, 4.75 h)	79.2° 18:20	11.25	90%	117.9°
2047-01-15 Tue	100	—	unknown	18:55–23:40 (good, 4.75 h)	79.2° 18:15	11.23	82%	131.5°
2047-01-16 Wed	100	—	unknown	18:55–23:40 (good, 4.75 h)	79.2° 18:15	11.21	72%	144.7°
2047-01-17 Thu	100	—	unknown	19:00–23:40 (good, 4.67 h)	79.2° 18:10	11.18	61%	156.9°
2047-01-18 Fri	100	—	unknown	19:00–23:40 (good, 4.67 h)	79.2° 18:05	11.16	50%	165.2°
2047-01-19 Sat	100	—	unknown	19:00–23:35 (good, 4.58 h)	79.2° 18:00	11.13	39%	162.9°
2047-01-20 Sun	100	—	unknown	19:00–23:30 (good, 4.5 h)	79.2° 18:00	11.11	28%	152.6°
2047-01-21 Mon	100	—	unknown	19:00–23:25 (good, 4.42 h)	79.2° 17:55	11.08	19%	140.2°
2047-01-22 Tue	100	—	unknown	19:05–23:20 (good, 4.25 h)	79.2° 17:50	11.06	11%	127.3°
2047-01-23 Wed	100	—	unknown	19:05–23:20 (good, 4.25 h)	79.2° 17:45	11.03	5%	114.4°
2047-01-24 Thu	100	—	unknown	19:05–23:15 (good, 4.17 h)	79.2° 17:40	11.0	1%	101.5°
2047-01-25 Fri	100	—	unknown	19:05–23:10 (good, 4.08 h)	79.2° 17:40	10.98	0%	88.8°
2047-01-26 Sat	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.2° 17:35	10.95	1%	76.3°
2047-01-27 Sun	100	—	unknown	19:10–23:05 (good, 3.92 h)	79.2° 17:30	10.92	4%	64.1°
2047-01-28 Mon	97	—	unknown	19:10–23:00 (good, 3.83 h)	79.2° 17:25	10.89	8%	52.2°
2047-01-29 Tue	88	—	unknown	19:10–22:55 (good, 3.75 h)	79.2° 17:20	10.86	14%	40.8°
2047-01-30 Wed	76	—	unknown	19:10–22:50 (good, 3.67 h)	79.2° 17:20	10.82	22%	30.0°
2047-01-31 Thu	63	—	unknown	19:15–22:35 (good, 3.33 h)	79.2° 17:15	10.79	30%	20.4°
2047-02-01 Fri	50	—	unknown	19:15–22:20 (good, 3.08 h)	79.2° 17:10	10.76	39%	14.5°
2047-02-02 Sat	39	—	unknown	19:15–20:50 (good, 1.58 h)	79.2° 17:05	10.73	48%	16.6°
2047-02-03 Sun	28	—	unknown	19:15–22:55 (marginal, 3.67 h)	79.2° 17:05	10.69	58%	25.0°
2047-02-04 Mon	22	—	unknown	19:15–22:40 (marginal, 3.42 h)	79.2° 17:00	10.66	67%	35.6°
2047-02-05 Tue	21	—	unknown	19:20–22:30 (marginal, 3.17 h)	79.2° 16:55	10.62	76%	47.2°
2047-02-06 Wed	22	—	unknown	19:20–22:25 (marginal, 3.08 h)	79.2° 16:50	10.59	84%	59.4°
2047-02-07 Thu	26	—	unknown	19:20–22:30 (marginal, 3.17 h)	79.2° 16:45	10.55	91%	72.1°
2047-02-08 Fri	33	—	unknown	19:20–20:15 (good, 0.92 h)	79.2° 16:45	10.52	96%	85.4°

Download: CSV · JSON

💡 API

curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&date=2047-01-10&days=30"
curl -sS "https://devops.majbase.com/rozhen-planner/calendar-api?target=M31&days=30&format=csv" -o m31-calendar.csv

One row per night: score_astronomy always, score_weather / score only where a forecast or history exists (null otherwise, with weather_source saying which), best window, dark hours, Moon illumination and separation, transit. 7–60 nights. Errors: 400 with invalid_date or target_unresolved. Results are cached for six hours; calculation version 2026-10-10.1.